4 stroke with sickbikeparts jackshaft

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indian22

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Dec 31, 2014
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Do you mean twist like move or twist like twisted metal?
Guys I'm getting confused with the terminology used for rear drop outs. Vertical dropouts allow the rear axle to be removed like the front fork, pretty much straight down. It's the axle style used for 21 speed etc. bikes with derail. drive trains for which it's wonderful, but it's lousy for single speed motor powered bikes p.m. me if you want to read the book of why this is.

The horizontal rear axle drop slot is parallel to the ground and the axle slips out by pulling straight to the rear of the frame. This allows easy wheel removal and allows two chain adjustment by simply altering the rear axle position. The slot for this is cut horizontally relative to the ground and the vertical drop is at 90 degrees relative to the ground. Chain adjustment can't be made by moving the axle in the vertical drop design as the axle is always locked into the drop slot.

Terms now defined: it's literally impossible for the rear axle to slip off on the vertical slot drop out. The axle could fall out if the bike got airborne and the axle was very loose, but it can't slip off unless the drop plate fractures and separates from the frame.... one in a billion chance that happens.

The horizontal slot that is preferred for motor bike construction, can come loose if not properly tightened, but as for the wheel falling off, not going to happen: if the chains are on and properly adjusted they will hold the wheel in the slot, and in addition if you are using a coaster brake the brake lever frame band will keep the wheel on. If you're not riding under the influence you should notice something is wrong back there long before damage occurs, the first major event would be chains breaking or one or both chains jumping sprocket. You should feel the bike getting wormy long before these things occur though.

Components located on the seat post that deal with drive train can't be allowed slip, twist or break. If you're not an accomplished welder hire one, some bolt on stuff is fine but typically pricy as well. Study forum builds that are designed like what you want to use and learn stuff, ask these builders what they used etc. Private message is usually the best way to get a response from forum members.

Have fun,

Rick C.
 

MotoMagz

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Yes Rick welding is best! But there are a few things u can do if you can’t get the welding done. Instead of the U bolt use another muffler clamp (s) base and some nice bolts lock washers and nuts.. the clamp is now 2 bases then if you can find a old fork or pipe you can cut in half the long way. Put these 2 pieces of pipe under clamps and you can tighten the **** out of it without crimping your seat post tube.Heres a picture of pipe under a normal clamp
 

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curtisfox

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Another way, but would have to be welded, or soldered, is like you said 2 pieces of pipe split. If it is in permeate location, weld one half to the post, then clamp. It still can move up and down some, but can't twist........Curt
 
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indian22

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Harley 3 piece tube clams.jpg


Yes Rick welding is best! But there are a few things u can do if you can’t get the welding done. Instead of the U bolt use another muffler clamp (s) base and some nice bolts lock washers and nuts.. the clamp is now 2 bases then if you can find a old fork or pipe you can cut in half the long way. Put these 2 pieces of pipe under clamps and you can tighten the **** out of it without crimping your seat post tube.Heres a picture of pipe under a normal clamp
Good tip Moto and tube crushing is what needs to be prevented using clamps the method you describe works really well, looks nice and is economical.

I typically insert and extra length of saddle tube inside the seat post to give added strength to the seat post and also prevent crushing of the post. I use a lot of Harley Davidson 3 piece tube clamps on 7/8", 1",1 1/8", 1 1/4" & 1 1/2" tubing with no kinking, but on the seat post I still use the extra saddle tube dropped inside the seat post for additional strength for the post. These clamps are 'kinda pricy but won't ever slip and because of their design won't crush even thin bike tubing. They really look nice as well.

So yes welding skill isn't always necessary to make a secure tube frame connection. If you have the equipment and skill it is the least expensive...and it's also quite strong.

Many solutions to a lot of our construction questions, just select one and do it.

Rick C.
 
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waynesdata

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Yes Rick welding is best! But there are a few things u can do if you can’t get the welding done. Instead of the U bolt use another muffler clamp (s) base and some nice bolts lock washers and nuts.. the clamp is now 2 bases then if you can find a old fork or pipe you can cut in half the long way. Put these 2 pieces of pipe under clamps and you can tighten the **** out of it without crimping your seat post tube.Heres a picture of pipe under a normal clamp

@ MotoMagz Has anything tried to move on your blue bike? Should be a good reference since that it basically what I am trying to build. Could jb weld be used on top of a bolt you want to NEVER come out?
 

xXNightRiderXx

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@ MotoMagz Has anything tried to move on your blue bike? Should be a good reference since that it basically what I am trying to build. Could jb weld be used on top of a bolt you want to NEVER come out?
It would be better to use blue threadlock. You will always want that bolt to come out at some point, and you don't want to have to go grinding away at JB Weld or blasting it with a torch if you use red threadlock when you do. Always think in terms of future maintenance, and what you can do to make it as easy on yourself as you can.
 
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indian22

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@ MotoMagz Has anything tried to move on your blue bike? Should be a good reference since that it basically what I am trying to build. Could jb weld be used on top of a bolt you want to NEVER come out?
No! I totally concur with Night riders view point.

Rick C.
 

waynesdata

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Been trying to find the specs for the engine I have, but there seems to be none, It's 79cc 4 stroke from the company called Gasbike, I bought it from Bikeberry.
I think gasbike built the kit with a 79cc predator engine. If true harborfreight would be a good place to start looking.

I am sure someone will chime in.
 
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indian22

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I think gasbike built the kit with a 79cc predator engine. If true harborfreight would be a good place to start looking.

I am sure someone will chime in.
Don't know what Gas bike uses , but that 79cc Predator from Harbor freight has been used a lot on bikes. With good reviews. 3 hp with good warranty, swap out, from HF it sure beats trying to get Gas bikes on the phone!

Rick C.